Revolving grate



H. G. LEE.

REVOLVING GRATE.

APPLICATION FILED 050.4.1911. RENEWED SEPT. 24, 1919.

Patented Nov. 4, 1919.

lzlllrllililv asv HARRY G. LEE, OF TACOMA, WASHINGTON.

REVOLVING GRATE.

Specification of Letters Patent.

Patented Nov. 4, 1919.

Application filed December 4, 1917, Serial No. 205,342. Renewed September 24, 1919. Serial No 325,964.

To all whom it may concern:

Be it known that I, HARRY G. LEE, a citizen of the United States, residing at Tacoma, in the county of Pierce and State of Washington, have invented certain new and useful Improvements in Revolving Grates, of

which the following is a specification.

The invention relates to grates particularly adapted for furnaces, and aims to secure a positive draft, to prevent the burning and warping of the grate bars, to free the fuel bed from ashes and clinkers, and to prevent obstructing of the grate bars.

The invention consists of hollow grate bars mounted to receive a rotary movement and strengthened and reinforced by longitudinal ribs which also serve to maintain mounted in a manner to positively direct the accumulations into the ash pit.

The invention furthermore consists of novel means for supplying air, steam or. like medium to the grate bars from a header or conduit common to all the grate bars, said header or conduit having clean-out openings opposite the several grate bars'which are covered by suitable closing means.

v For a full understanding of the invention and the merits thereof, reference is'to be had to the following description and the drawings hereto attached, in which- Figure 1 is an elevation of a furnace grate embodying the invention, parts being broken away, and partly in section.

Fig. 2 is a front view, parts being broken away.

Fig. 3 is a sectional detail showing the parts on a larger scale.

Fig. 1 is a sectional detail of the rear por- 2, fire chamber 3 and an .ash pit 4. The

bridge wall 2 is formed init forward side with a recess, the bottom wall 5 of which inclines forwardly anddownwardly so as to direct ashes and other accumulations discharged from the rear of the grate bars into the ash pit 4. 1

The grate may comprise any number of bars 6 which may be of any length or diam eter, and which are hollow and mounted in a manner to receive a rotary movement. As indicated in Fig. 1, the grate bars 6 are mounted at their ends and intermediate their ends. To reduce the friction to the smallest amount possible, the bearings are preferably ofthe anti-friction type, and are shown as comprising rollers. Each of :the grate bars is formed upon its outer surface with a plurality of longitudinally. disposed ribs 7 which serve to reinforce and strengthen the, gratebar, as also to preserve air spaces, and to engage and'p'ositively crush clinkers and insure a discharge of ashes and other matter, so as to maintain a fuel bed containing a minimum amount of-ashes, clinkers' and the like. The ribs 7 are formed at intervals in their lengthwith openings 8 for the escape of air, steam or other medium supplied to the grate bars'for promoting combustion of the fuel. The grate bars are open throughout their length and the rear of each grate bar has an outstanding flange 9 against which the plate 10 closes, being yieldably pressed forward by means of eXpansible yieldable springsll, whichv are mounted on guide rods 12' projecting rearwardly from the grate bar. ;A yoke'13 receives the rear ends of the guide. rods 12 and holds them in given position. The springs 11 are supported on the guide rod 12 and the latterlikewise support the plate or closure 10. c

A header or conduit 14 is disposedv in front of the furnace and extends transverselyth'e'reof, and is provided in its front side with a plurality of openings 15 in line.

with the respective grate bars 6. -,.The open ings 15' are closed by, suitable covers. 16.

Each ofithe grate bars, is provided at, its

outer or forward end with, a hollow journal 17 which is'mounted in the rear side of the header or conduit 14. The hollow journal 17 may. be provided in any manner,

7 either as a part of thegrate bar or as a tube secured thereto. A stuffing bo'x 18 of approved construction cooperateswith each of opened-throughout its'length, a closure for the hollow journals 17 to maintain a close joint between the journal and header. A

gear wheel 19 is secured to the projectinggrate bars and cooperates with a pawl 21 mounted upon a lever 22, which is support- "ed upon the journal of the grate bar pro 141 through the hollow journals 17 intothe respective grate bars, and escapes through I .the openings 8 thereof into the fuel bed vided with the ratchet wheel 20. The lever 22 may be operated in any manner and may be Connected with a moving part by means of a rod or like connection 23.

The header or conduit 14 is adapted to be connected with a blower or other source of fluid supply, such as steam or compressed air. The compressed air or other fluid medium passes through the header or conduit and promotes combustion as will be readily understood. In the event of ashes or other material accumulating in the grate bars, the

latter may be cleaned by introducing a a "brush or other device through the openings 15 of the header and passing such brush or cleaner through the grate bars, the closure 10 yielding to admit of-the ashes orothermaterial escaping and passing into the ash l pit in the manner herein stated. The grate the fuelbed; By closing the ash pit, the air is caused to pass therefrom through the bars may be rotated by. hand or by suitable mechanism, and in the event. of the furnace being fed by means of a mechanical stoker, the rod or part 23 may be connected to a moving part of the mechanism so as to im- 1 part a regular oscillatory movement to the lever 22,whereby the grate bars are slowly rotated so as to keep the fuel bed clear of ashes and clinkers.

It is observedthat practically as much air will enter the ash pit'as is directed through fire and the draft m be regulatedby causing the fan blower torotate at a greater "or v blower.

holding "closure seated, q

less speed this-means thefire may be forced, if necessary, by speeding'the fan I claim:: K

11A" 'hollowagrate bar provided in its length with a "pluralityf'of outlets and coveringthe rear end of'the grate bar, a guide for-supportingthe closure and a v. spring mountedon'saifd guideand'yieldably 2. A hollow. grate bar open throughout its length and provided with a plurality of lateral outlets, guide rods projecting from the rear of the grate bar, the closure mounted upon the guide rods and normally covering the rear end of the'grate and springs mounted upon the guide rods and normally exerting a pressure to hold the closure seated against the rear end of the grate bar.

8. A furnace embodying a wall at the rear of the fire chamber, said wall having a recess in its forward side with its bottom for wardly and downwardly inclined, a'hollow grate bar open throughout its length and having its rear endamounted in the recess of the inner wall, and a closure yieldably held against'the rear end of the grate bar to normally cover the same. t

4. A furnace grate comprising a plurality of hollow grate bars having discharge openings at their rear'ends and provided in their length with a' plurality of lateral outlets, closures normally covering the rear ends of "the grate bars, a header'connecting the front ends of the grate bars and in communication therewith and provided in its front side-with a plurality of openings in line with the openings of the respective grate bars, and closures for the openings of the header.

5. A furnace embodying a wall at the rear of the'fire chamber, said wall having a recess in its forward side with its bottom forwardly and downwardly declined, a hollow grate bar open throughout its length and provided with a lateral outlet intermediate its ends and having its rear end mounted in the recess of theinner wall. and a closure to normally cover the rear end ofthe grate bar.

6.A furnace embodying a bridge wall formed in its forward side with a recess having a forwardly and downwardly, in-' clined bottom discharging into the ash pit, a plurality of hollow grate bars rotatably mounted inthe front and bridgewalls of 1 the furnace and having openings in their length and a discharge opening at the rear,

a closure yieldably held against the rear end of each grate bar and disposed within the recess ofthe bridge wall, means connecting the grate'bars to cause them to rotate in unison, a header provided in its front side with openings opposite the respective grate bars, closures jforsuch openings, and hollowjournals forming connecting means between the respective grate bars and the" header. a I a In testimony whereof I aflix my signature. Gr. LEE.

. Copies. of this patent may be obtained'for five cents each, by addressing the Q ommissioner of latents,

-; r Washington, D. 0. v 

